Aspects of the present disclosure relate generally to systems and networks of optical cables, which may include optical fibers to transmit and receive signals. More specifically, some aspects of the present disclosure relate to optical cable systems that include integrated signal loopback features.
Network deployments for governments or other entities, such as components of the US Federal Government, may require high security. Protected Distribution Systems (PDS) networks have strict requirements for cable protection and wiretapping prevention. For example, some such systems have sealed, exposed conduits that can be visually inspected for tampering. However, such systems tend to be very expensive as well as unsightly in office environments.
Other intrusion monitoring systems have been developed that monitor an optical cable for movement or tampering by monitoring changes in light patterns of signals communicated via the optical cable. Such intrusion monitoring systems typically rely upon loopback devices or assemblies that return a signal from the source (i.e., loop the signal back). Distortions or changes in return signals may indicate intrusion. Such intrusion monitoring systems employing loopback devices or assemblies may eliminate a need for exposed, hardened conduits.
However, connection schemes that employ the loopback intrusion monitoring systems may be bulky and complex, often requiring mechanical connections of loopback channels on ends of cables. For example, loopbacks may be formed by attaching connectors to two fibers on the end of a cable, using adapters and a bridge fiber with two more connectors to connect the two fibers of the cable. The connections result in attenuation losses in the loopback signals as well as provide a source for assembly error, particularly in complex networks.
A need exists for a secure intrusion monitoring system that can be efficiently deployed in an office or data center environment, that takes up little space, and/or that allows for easy assembly in complex networks while limiting the ability of potential intruders to tap the network.